Why come there was never a tv reunion movie of the cosby show in the 90's or even in the early 200's while everybody was still young and fresh ???

https://www.youtube.com/watch?v=n3eJkf4erbI
https://www.youtube.com/watch?v=n3eJkf4erbI
https://www.youtube.com/watch?v=n3eJkf4erbI